System is the original system in use on a Mac. It is a very basic, graphical only system which is only available in black and white.
There are many versions of the system available, growing slightly as they get on.
System 1, 2, 3 and 4
System 1 is the original version of the software trying to make a impact. Versions 1, 2, 3 and 4 are relatively the same, the next growing a new feature or two but nothing much. The System used the Macintosh File System, which was really poor as it wasn't well done.
- System 1 was the base release
- System 2 included a Finder update
- System 3 was introduced on the Mac Plus
- System 4 introduced AppleShare (now it's just binned).
System 5 included a multi-tasking system called "MultiFinder" which was really very basic and was able to be switched off and it acted just like System 4.
System 6 is put as the first stable and long lasting operating system around. It mainly included hardware updates which included support for a new processor, 1.44mb SuperDrive and special features in the Macintosh Portable.
System 7 was the first major change in the system, making it ready for the Mac OS system which overtook the name in release 7.6. It was mainly to make the system work smoother, look better and support better hardware.